Adjusting Sound on a Medical Device

ABSTRACT

A dialysis machine comprising: a microphone; an alert module for producing an audible alert related to an operating condition of the dialysis machine; and a processing module configured for: receiving, from the microphone, information related to measured noise; determining, based on the information related to measured noise, an audible alert that will not be masked by the measured noise when the audible alert is produced by the alert module; and providing, to the alert module, instructions for producing the audible alert.

TECHNICAL FIELD

This disclosure relates to adjusting sound on a medical device.

BACKGROUND

Dialysis is a treatment used to support a patient with insufficientrenal function. Dialysis machines typically include audio output devicesthat can be used to alert nurses or doctors of events related to thedialysis treatment. For example, some dialysis machines output an audiotone that corresponds to an alarm condition.

SUMMARY

In one aspect, a dialysis machine includes a microphone. The dialysismachine also includes an alert module for producing an audible alertrelated to an operating condition of the dialysis machine. The dialysismachine also includes a processing module configured for receiving, fromthe microphone, information related to measured noise. The processingmodule is also configured for determining, based on the informationrelated to measured noise, an audible alert that will not be masked bythe measured noise when the audible alert is produced by the alertmodule. The processing module is also configured for providing, to thealert module, instructions for producing the audible alert.

Implementations can include one or more of the following features.

In some implementations, the processing module is configured to identifya type of the measured noise.

In some implementations, the measured noise is ambient noise.

In some implementations, the measured noise is a second audible alert.

In some implementations, the second audible alert is related to anoperating condition of a second dialysis machine.

In some implementations, the information related to the ambient noiseincludes a measurement of a volume of the ambient noise.

In some implementations, the instructions cause the alert module toproduce an audible alert that is louder than the volume of the ambientnoise.

In some implementations, the information related to the second audiblealert includes a measurement of a timing of the second audible alert.

In some implementations, the instructions cause the alert module toproduce an audible alert that has a timing that is out of phase with thetiming of the second audible alert.

In some implementations, the information related to the second audiblealert includes a measurement of a frequency of the second audible alert.

In some implementations, the instructions cause the alert module toproduce an audible alert of a frequency different from the frequency ofthe second audible alert.

In some implementations, the audible alert has a frequency that iswithin a predefined range.

In some implementations, the instructions for producing the audiblealert are based at least in part on the type of the measured noise.

In some implementations, the instructions for producing the audiblealert are based at least in part on the priority of the audible alert.

In some implementations, the instructions cause the alert module toproduce an audible alert that is louder than lower-priority audiblealerts that are measured by the microphone.

In another aspect, a method includes receiving, from a microphone of adialysis machine, information related to measured noise. The method alsoincludes determining, based on the information related to measurednoise, an audible alert related to an operating condition of thedialysis machine. The audible alert is determined such that the audiblealert will not be masked by the measured noise when the audible alert isproduced by an alert module of the dialysis machine. The method alsoincludes providing, to the alert module, instructions for producing theaudible alert.

In another aspect, a system includes a dialysis machine. The dialysismachine includes a microphone. The dialysis machine also includes analert module for producing an audible alert related to an operatingcondition of the dialysis machine. The dialysis machine also includes aprocessing module configured for receiving, from the microphone,information related to measured noise. The processing module is alsoconfigured for determining, based on the information related to measurednoise, an audible alert that will not be masked by the measured noisewhen the audible alert is produced by the alert module. The processingmodule is also configured for providing, to the alert module,instructions for producing the audible alert.

In another aspect, a computer-readable storage device storing a computerprogram includes instructions for causing a computer to receive, from amicrophone of the dialysis machine, information related to measurednoise. The computer program also includes instructions for causing thecomputer to determine, based on the information related to measurednoise, an audible alert related to an operating condition of thedialysis machine. The audible alert is determined such that the audiblealert will not be masked by the measured noise when the audible alert isproduced by an alert module of the dialysis machine. The computerprogram also includes instructions for causing the computer to provide,to the alert module, instructions for producing the audible alert.

Implementations can include one or more of the following advantages.

In some implementations, the volume of the audible alert can be adjustedsuch that it is not unnecessarily loud for the particular environmentalnoise conditions.

In some implementations, the volume of the audible alert can be adjustedsuch that it can be heard over environmental noise.

In some implementations, the timing of the audible alert can be adjustedsuch that it is out of phase with one or more other audible alerts(e.g., from other dialysis machines).

In some implementations, the frequency (e.g., pitch) of the audiblealert can be adjusted such that the audible alert is not masked by oneor more other audible alerts (e.g., from other dialysis machines).

Other aspects, features, and advantages of the invention will beapparent from the description and drawings, and from the claims.

DESCRIPTION OF DRAWINGS

FIG. 1 is a front perspective view of a hemodialysis system, including aspeaker and a microphone.

FIG. 2 shows examples of alarm signals having different priorities.

FIG. 3a shows an example of a hemodialysis system that is in arelatively quiet environment.

FIG. 3b shows an example of a hemodialysis system that is in arelatively noisy environment.

FIG. 4 shows an example of hemodialysis systems that are within audiblerange of each other.

FIG. 5 shows an example of a timing-adjusted alarm signal.

FIG. 6 shows an example of a frequency-adjusted alarm signal.

DETAILED DESCRIPTION

Dialysis machines typically use audible sounds as alerts for variousoperating conditions. For example, when a dialysis machine detects acondition that requires the attention of a human being, the dialysismachine may play a sound than an operator may recognize as associatedwith either the specific condition or error conditions in general. In anoisy environment, these audible alerts may be drowned out by ambientnoise. Similarly, if multiple dialysis machines are in the samelocation, an audible alert from one dialysis machine may be masked byaudible alerts from other dialysis machines.

A dialysis machine can be configured to adapt its audio output based onthe audio characteristics of its environment. A particular dialysismachine can include a microphone for measuring ambient noise and audiblealerts from other dialysis machines. A processing module can analyze thesound measurements to determine whether the ambient noise and theaudible alerts from other dialysis machines are interfering with theaudible alerts of the particular dialysis machine. If appropriate, thedialysis machine can make adjustments to its audible alert so that theaudible alert can be perceived over the ambient noise and the audiblealerts from other dialysis machines.

One technique that a dialysis machine can use is the adjustment of itsoutput volume. In some examples, if the processing module determinesthat ambient noise is downing out the dialysis machine's audible alerts,the volume of the audible alerts can be automatically increased.Similarly, if the processing module determines that there is very littleambient noise, the volume of the audible alerts can be automaticallydecreased.

Another technique that a dialysis machine can use is the adjustment ofthe timing of its audio output signal. In some examples, if theprocessing module determines that audible alerts from other dialysismachines are masking the particular dialysis machine's audible alert,the timing of the particular dialysis machine's audible alert can beadjusted. For example, assuming that the audible alerts are made up ofrepetitive beeps, the audible alert of the particular dialysis machinecan be adjusted such that the beeps are out of phase with the beeps ofthe audible alerts from the other dialysis machines.

Yet another technique that a dialysis machine can use is the adjustmentof the frequency of its audio output signal. In some situations, onesound may mask another sound if the frequencies of the two soundsinterfere with each another. If the processing module determines thatfrequencies of audible alerts from other dialysis machines are causingthe particular dialysis machine's audible alert to be masked, thefrequency of the particular dialysis machine's audible alert can beadjusted.

FIG. 1 shows a hemodialysis system 100 configured to adapt its audiooutput based on audio conditions of its environment. The hemodialysissystem 100 includes a hemodialysis machine 102 to which a disposableblood component set 104 that forms a blood circuit is connected. Duringhemodialysis, arterial and venous patient lines 106, 108 of the bloodcomponent set 104 are connected to a patient and blood is circulatedthrough various blood lines and components, including a dialyzer 110, ofthe blood component set 104. At the same time, dialysate is circulatedthrough a dialysate circuit formed by the dialyzer 110 and various otherdialysate components and dialysate lines connected to the hemodialysismachine 102. Many of these dialysate components and dialysate lines arelocated inside the housing 103 of the hemodialysis machine 102, and arethus not visible in FIG. 1. The dialysate passes through the dialyzer110 along with the blood. The blood and dialysate passing through thedialyzer 110 are separated from one another by a semi-permeablestructure (e.g., a semi-permeable membrane and/or semi-permeablemicrotubes) of the dialyzer 110. As a result of this arrangement, toxinsare removed from the patient's blood and collected in the dialysate. Thefiltered blood exiting the dialyzer 110 is returned to the patient. Thedialysate that exits the dialyzer 110 includes toxins removed from theblood and is commonly referred to as “spent dialysate.” The spentdialysate is routed from the dialyzer 110 to a drain.

One of the components of the blood component set 104 is an air releasedevice 112. The air release device 112 includes a self-sealing ventassembly that allows air to pass therethrough while inhibiting (e.g.,preventing) liquid from passing therethrough. As a result, if bloodpassing through the blood circuit during treatment contains air, the airwill be vented to atmosphere as the blood passes through the air releasedevice 112.

As shown in FIG. 1, a dialysate container 124 is connected to thehemodialysis machine 102 via a dialysate supply line 126. A drain line128 and an ultrafiltration line 129 also extend from the hemodialysismachine 102. The dialysate supply line 126, the drain line 128, and theultrafiltration line 129 are fluidly connected to the various dialysatecomponents and dialysate lines inside the housing 103 of thehemodialysis machine 102 that form part of the dialysate circuit. Duringhemodialysis, the dialysate supply line 126 carries fresh dialysate fromthe dialysate container 124 to the portion of the dialysate circuitlocated inside the hemodialysis machine 102. As noted above, the freshdialysate is circulated through various dialysate lines and dialysatecomponents, including the dialyzer 110, that form the dialysate circuit.As the dialysate passes through the dialyzer 110, it collects toxinsfrom the patient's blood. The resulting spent dialysate is carried fromthe dialysate circuit to a drain via the drain line 128. Whenultrafiltration is performed during treatment, a combination of thespent dialysate and excess fluid drawn from the patient is carried tothe drain via the ultrafiltration line 129.

The blood component set 104 is secured to a module 130 attached to thefront of the hemodialysis machine 102. The module 130 includes a bloodpump 132 capable of driving blood through the blood circuit. The module130 also includes various other instruments capable of monitoring theblood flowing through the blood circuit. The module 130 includes a doorthat when closed, as shown in FIG. 1, cooperates with the front face ofthe module 130 to form a compartment sized and shaped to receive theblood component set 104. In the closed position, the door pressescertain blood components of the blood component set 104 againstcorresponding instruments exposed on the front face of the module 130.As described in greater detail below, this arrangement facilitatescontrol of the flow of blood through the blood circuit and monitoring ofthe blood flowing through the blood circuit.

The blood pump 132 can be controlled by a blood pump module 134. Theblood pump module 134 includes a display window, a start/stop key, an upkey, a down key, a level adjust key, and an arterial pressure port. Thedisplay window displays the blood flow rate setting during blood pumpoperation. The start/stop key starts and stops the blood pump 132. Theup and down keys increase and decrease the speed of the blood pump 132.The level adjust key raises a level of fluid in an arterial dripchamber.

A drug pump 192 also extends from the front of the hemodialysis machine102. The drug pump 192 is a syringe pump that includes a clampingmechanism configured to retain a syringe 178 of the blood component set104. The drug pump 192 also includes a stepper motor configured to movethe plunger of the syringe 178 along the axis of the syringe 178. Ashaft of the stepper motor is secured to the plunger in a manner suchthat when the stepper motor is operated in a first direction, the shaftforces the plunger into the syringe, and when operated in a seconddirection, the shaft pulls the plunger out of the syringe 178. The drugpump 192 can thus be used to inject a liquid drug (e.g., heparin) fromthe syringe 178 into the blood circuit via a drug delivery line 174during use, or to draw liquid from the blood circuit into the syringe178 via the drug delivery line 174 during use.

The hemodialysis machine 102 includes an alert module such as a speaker101, an audio input device such as a microphone 105, a touch screen 118and a control panel 120. The touch screen 118 and the control panel 120allow the operator to input various different treatment parameters tothe hemodialysis machine 102 and to otherwise control the hemodialysismachine 102. In addition, the touch screen 118 serves as a display toconvey information to the operator of the hemodialysis system 100. Inthe example shown in FIG. 1, the speaker 101 and the microphone 105 arepositioned below the touch screen 118 and together function to providecustomized audio signals (e.g., as alerts) to the operator of the system100. Thus, the hemodialysis machine 102 is capable of providing bothvisual alerts via the touch screen 118 and customized audio alerts viathe speaker 101 to the operator of the system 100 during use.

The hemodialysis machine 102 includes a processing module 107 thatresides inside the machine and which is connected to the touch screen118, the control panel 120, the speaker 101, and the microphone 105. Theprocessing module 107 is configured to receive data that is input viathe touch screen 118 and the control panel 120 and control thehemodialysis machine 102 based on the received data. For example, theprocessing module 107 can adjust the operating parameters of thehemodialysis machine 102. The processing module 107 is also configuredto provide instructions to the speaker 101 based on the operatingparameters of the hemodialysis machine 102 and information related tomeasured noise. The information related to measured noise can be in theform of audio data received from the microphone 105. In some examples,if the processing module 107 determines that a condition exists thatrequires that an alert be sound, the processing module 107 can provideinstructions to the speaker 101 that cause the speaker 101 to sound analert. Further, if the audio data received from the microphone 105indicate that the alert may not be effectively heard by an individual inproximity, the processing module 107 can cause the speaker 101 to adjustthe alert accordingly such that the audible alert will not be masked bythe measured noise.

Alerts can take on different forms depending on the triggeringcondition. In some examples, alerts can be split up into multiplegroups. FIG. 2 shows an example of three alarm signals having threedifferent priorities: a high priority alarm signal 202, a mediumpriority alarm signal 204, and a low priority alarm signal 206. Thealarm signals can be related to various health conditions of thepatient, such as cardiovascular conditions, oxygenation conditions,ventilation conditions, temperature conditions, drug deliveryconditions, fluid delivery conditions, or artificial perfusionconditions. The alarm signals can also be related to various conditionsor states of the hemodialysis machine 102. For example, an alarm signalmay indicate that the hemodialysis machine 102 is in a “general” or“advisory” state. In some examples, an alarm signal may indicate thatthe hemodialysis machine 102 is in a power-up, a power-down, or a powerfailure state.

Each alarm signal 202, 204, 206 can include one or more bursts. The highpriority alarm signal 202 includes at least two bursts 208. The mediumpriority alarm signal 204 includes at least two bursts 210. The lowpriority alarm signal 206 includes at least one burst 212. A secondburst 212 is optional. In some examples, low priority alarm signals onlyinclude a single burst.

Each burst 208, 210, 212 includes one or more notes 214 (sometimesreferred to as pulses), each of which has an effective pulse durationt_(d). The t_(d) can have a value of 75 ms to 200 ms for the highpriority alarm signal 202 and a value of 125 ms to 250 ms for the mediumpriority 204 and low priority 206 alarm signals.

Each burst 208 a, 208 b of the high priority alarm signal 202 includes apattern of five notes 216 played twice, totaling ten notes in eachburst. Each burst of the medium priority alarm signal 204 includes apattern of three notes. Each burst (if there is more than one burst) ofthe low priority alarm signal 206 includes a pattern of two notes. Insome examples, low priority alarm signals only include a single note ineach burst.

Bursts 208, 210, 212 of the alarm signals can be separated by a periodof time, the length of which can depend on the priority of the alarm.For example, the interburst interval (t_(b)) for the high priority alarmsignal 202 can be 2.5 to 15 seconds, the t_(b) for the medium priorityalarm signal 204 can be 2.5 to 30 seconds, and the t_(b) for the lowpriority alarm signal 206 can be greater than 15 seconds. In someexamples, low priority alarm signals do not repeat (e.g., they onlysound once), so there is no t_(b).

The notes 214 of the alarms are separated by a period of time, thelength of which can depend on the priority of the alarm. Referring tothe high priority alarm signal 202, the first and second notes, thesecond and third notes, and the fourth and fifth notes of each five-notepattern 216 are separated by a period of time x. The period of time xcan have a value between 50 ms and 125 ms. The third and fourth notes ofeach five-note pattern 216 are separated by a period of time 2x+t_(d).Successive five-note patterns 216 are separated by a period of timet_(p). The period of time t_(p) can have a value of 0.35 s to 1.3 s.Referring to the medium priority alarm signal 204, the first and secondnotes and the second and third notes of each burst 210 are separated bya period of time y. The period of time y can have a value between 125 msand 250 ms. Referring to the low priority alarm signal 206, the firstand second notes (if there is a second note) of each burst 212 areseparated by the period of time y.

Irrespective of the priority of an alarm signal, the pitch of an alarmsignal can indicate the condition or event that triggered the alarm. Inthis way, two alarm signals can be distinguished based on the pitch ofthe signal. For example, a general alarm may have a fixed pitch (e.g.,each note/pulse of the alarm has the same frequency of vibration), whilean oxygen alarm may have falling pitches (e.g., each note/pulse of thealarm has a frequency of vibration that is less than the precedingnote). The pitch may be expressed as a musical tone that has a relativeposition on a musical scale. In an example of a medium priority generalalarm signal, the pitch of the notes may be three successive “C” notes,while in an example of a medium priority oxygen alarm, the pitch may be“C” for the first note, “B” for the second note, and “A” for the thirdnote. Additional notes may be included in the alarm signal depending onthe priority of the alarm. In an example of a high priority generalalarm signal, the pitch of the notes may be five successive “C” notes,while in an example of a high priority oxygen alarm, the pitch may be“C” for the first note, “B” for the second note, “A” for the third note,“G” for the fourth note, and “F” for the fifth note. In this example,the “G” note and the “F” note are one octave lower than the octave ofthe first three notes, thereby resulting in five notes with fallingpitches.

In addition to the timing and pitch, the amplitude (sometimes referredto informally as volume) of the notes in an alarm signal can be used toconvey information to the operator of the hemodialysis system 100. Theamplitude of the notes of an alarm signal (signified by the variable “a”in FIG. 2) can depend on the priority of the particular alarm signal.For example, still referring to FIG. 2, the notes 214 of the highpriority alarm signal 202 have a larger amplitude than the amplitude ofthe notes 214 of the medium priority alarm signal 204, and the notes 214of the medium priority alarm signal 204 have a larger amplitude than theamplitude of the notes 214 of the low priority alarm signal 206. Assuch, the high priority alarm signal 202 is louder than the other twoalarm signals 204, 206 and is more likely to be heard.

The values for the variables a, x, y, t_(b), t_(d), and t_(p) may bemandated, e.g., by guidelines created and/or published by a standardsorganization. In some examples, the values for the variables aremandated by the International Organization for Standardization (ISO)and/or the International Electrotechnical Commission (IEC). In someexamples, the values for the variables conform to IEC 60601-1-8standards.

In some implementations, it may be desirable to adjust characteristicsof an alarm signal for a number of reasons. For example, thecharacteristics of an alarm signal can be adjusted based on the amountof ambient noise measured in a room. FIG. 3a shows an example of ahemodialysis system 100 that is in a relatively quiet environment. Thehemodialysis system 100 may be, for example, in a quiet wing of ahospital or in a room occupied by only the single patient. An operatorof the hemodialysis machine 102 may prefer that the volume of an alarmsignal 304 a is reduced so that the patient is not startled when analarm is activated. The operator need not manually adjust the volume ofthe alarm signal 304 a that will be emitted by the speaker 101. Instead,the hemodialysis machine 102 is configured to measure ambient noise 302a and automatically adjust the volume of the alarm signal accordingly.The microphone 105 measures ambient noise 302 a and provides audio datato the processing module 107. In this example, the ambient noise 302 ais relatively quiet (e.g., the amplitude of the ambient noise 302 a isrelatively small, 20 dB). The processing module 107 analyzes the audiodata and determines an appropriate volume for the alarm signal 304 a. Inthis example, because the ambient noise 302 a is relatively quiet, theprocessing module 107 determines that an alarm signal 304 a having anamplitude of 50 dB is sufficient and appropriate. The processing module107 instructs the speaker 101 to sound the alarm signal 304 a at thecomputed amplitude of 50 dB. The processing module 107 may use analgorithm to determine the appropriate amplitude for the alarm signal304 a. In some implementations, the appropriate amplitude for the alarmsignal 304 a is based at least in part on guidelines and/or standardscreated or enforced by a regulatory body.

FIG. 3b shows an example of a hemodialysis system 100 that is in arelatively noisy environment. The hemodialysis system 100 may be, forexample, in a communal area of a hospital or in a room occupied bymultiple patients (e.g., in a dialysis clinic). The operator of thehemodialysis machine 102 may want the volume of an alarm signal 304 b tobe increased so that the operator can hear the alarm over ambient noise302 b. The microphone 105 measures the ambient noise 302 b and providesaudio data to the processing module 107. In this example, the ambientnoise 302 b is relatively loud (e.g., the amplitude of the ambient noise302 b is relatively large, 50 dB). The processing module 107 analyzesthe audio data and determines an appropriate volume for the alarm signal304 b. In this example, because the ambient noise 302 b is relativelyloud, the processing module 107 determines that an alarm signal 304 bhaving an amplitude of 70 dB is sufficient and appropriate. Theprocessing module 107 instructs the speaker 101 to sound the alarmsignal 304 b at the computed amplitude of 70 dB.

Other characteristics of an alarm signal can also be adjusted instead ofor in addition to the volume. In some implementations, multiplehemodialysis systems are located in relatively close proximity to eachother. If two or more hemodialysis machines are emitting alarm signalsat the same time, one or more of the alarm signals may be masked (e.g.,drowned out) by the other.

FIG. 4 shows an example of two hemodialysis systems 100 a, 100 b thatare within audible range of each other. The speakers 101 a, 101 b areemitting respective alarm signals 402 a, 402 b. In this example, thealarm signals 402 a, 402 b are masking each other. The notes 214 of thealarm signal 402 a from one hemodialysis system 100 a sound at the sametimes (t_(o), t₁, . . . t_(n)) as the notes 214 of the alarm signal 402b from the other hemodialysis system 100 b. As such, an operator of thehemodialysis systems 100 a, 100 b may be unable to discern between thetwo alarm signals 402 a, 402 b. One technique that can be used to remedythis issue is to adjust the volume of one of the alarm signals in asimilar manner as described above with reference to FIG. 3b . However,doing so would simply allow the adjusted alarm signal (e.g., 402 a) tobe heard over the unadjusted alarm signal (e.g., 402 b) while furthermasking the unadjusted alarm signal. Instead, the timings of one or bothof the alarm signals 402 a, 402 b can be adjusted so that the two alarmsignals 402 a, 402 b are out of sync, thus allowing a listener to betterhear both alarm signals simultaneously.

FIG. 5 shows an example of an alarm signal 502 a that has note timingsdefined such that the alarm signal 502 a is not masked by a differentalarm signal 502 b. The speaker 101 b of one of the hemodialysis systems100 b plays an alarm signal 502 b. The microphone 105 a of the otherhemodialysis system 100 a measures the alarm signal 502 b and providesaudio data to the processing module 107. The processing module 107 alsodetermines that an alarm condition exists in the hemodialysis system 100a, and thus an alarm signal should be emitted by the speaker 101 a. Theprocessing module 107 analyzes the audio data and determines appropriatetimings for the alarm signal 502 a. In this example, the processingmodule 107 determines that the alarm signal 502 b from the otherhemodialysis system 100 b has a period of silence between bursts that isdefined by the interburst interval (t_(b)). The processing module 107determines that the bursts of the alarm signal 502 a from thehemodialysis system 100 a should occur during the t_(b) of the alarmsignal 502 b from the other hemodialysis system 100 b, and theprocessing module 107 instructs the speaker 101 a to sound the bursts ofthe alarm signal 502 a at the determined time windows. In this way, bothalarm signals 502 a, 502 b can be better discerned by the operator ofthe hemodialysis systems 100 a, 100 b.

In some implementations, if two or more hemodialysis machines areemitting alarm signals at the same time, the frequencies (sometimesinformally referred to as pitch) of one or both of the alarm signals canbe adjusted so that the operator can better discern the two alarmsignals. FIG. 6 shows an example of an alarm signal 602 a that has hadits frequency defined such that the alarm signal 602 a is not masked bya different alarm signal 602 b. In this example, the alarm signals 602a, 602 b are represented according to their relative frequencies asindicated by the waveform of each note 214. The speaker 101 b of one ofthe hemodialysis systems 100 b plays an alarm signal 602 b. Themicrophone 105 a of the other hemodialysis system 100 a measures thealarm signal 602 b and provides audio data to the processing module 107.The processing module 107 also determines that an alarm condition existsin the hemodialysis system 100 a, and thus an alarm signal needs to beemitted by the speaker 101 a. The processing module 107 analyzes theaudio data and determines an appropriate frequency for the alarm signal502 a. In this example, the processing module 107 determines that thealarm signal 502 b from the other hemodialysis system 100 b has afrequency f_(b). The processing module 107 determines that an alarmsignal 602 a with a frequency of f_(a) would not be masked by the alarmsignal 602 b from the other hemodialysis system 100 b. The processingmodule 107 instructs the speaker 101 a to sound an alarm signal 602 awith the defined frequency f_(a). In this way, both alarm signals 602 a,602 b can be discerned by the operator of the hemodialysis systems 100a, 100 b.

As described above, the pitch of an alarm signal can indicate thecondition or event that triggered the alarm. In this way, the musicaltones of the notes of an alarm signal can convey information to theoperator. As such, in some implementations, the processing module 107may consider a type of an alarm signal when defining an appropriatefrequency to prevent masking. For example, a relatively important alarm(e.g., an alarm indicating a potentially lethal cardiovascular conditionof the dialysis patient) may include one or more notes havinghigh-pitched frequencies that are designed to be audibly distinctive.The processing module 107 may be configured to only adjust the frequencyof the cardiovascular alarm to a frequency that resides within apredefined range to prevent the cardiovascular alarm from losing itsdistinctive pitch. In some implementations, the processing module 107may be configured to instruct another hemodialysis system (e.g., ahemodialysis system that is emitting a masking alarm signal) to adjustits own alarm signal. In this way, the alarm signal that ends up beingadjusted may be determined according to the relative importance of thealarm signals.

In some implementations, the processing module 107 can be configured toidentify generally what type of noise the microphone 105 is measuring.For example, the processing module 107 can identify whether the measurednoise is ambient noise or an alarm signal, e.g., by comparing themeasured noise to stored profiles representing the audio of known alarmsignals. The type of the measured noise may impact the manner in whichthe processing module 107 adjusts the alarm signals of the hemodialysismachine 100. For example, if the processing module 107 identifies themeasured noise as environmental noise, the processing module 107 mayadjust the volume of the emitted alarm. On the other hand, if theprocessing module 107 identifies the measured noise as an alarm signal,the processing module 107 may adjust the timing or the frequency of theemitted alarm.

A method of using the hemodialysis system 100 to administer a dialysistreatment to a patient will now be described.

Before treatment begins, an operator enters information into thehemodialysis machine 102 via the touch screen 118 and/or the controlpanel 120. The operator typically enters patient parameters and medicaltreatment information, and the hemodialysis machine 102 determinesappropriate operating parameters for the patient's treatment. Once thepatient parameters and the medical treatment information are entered,the operator prepares the patient for dialysis treatment. Referring backto FIG. 1, the arterial and venous patient lines 106, 108 are connectedto the patient, and hemodialysis is initiated. During hemodialysis,blood is circulated through the blood circuit (i.e., the various bloodlines and blood components, including the dialyzer 110, of the bloodcomponent set 104). At the same time, dialysate is circulated throughthe dialysate circuit (i.e., the various dialysate lines and dialysatecomponents, including the dialyzer 110).

During treatment, one or more alarm conditions may arise. For example,the hemodialysis machine 102 may detect a problem with the power source.The processing module 107 may determine that a power failure alarmsignal should be sounded. Before sounding the power failure alarmsignal, the processing module 107 may receive audio data from themicrophone 105.

In one example, the audio data may indicate that there is minimalenvironmental noise detected, and the processing module 107 can instructthe speaker 101 of the hemodialysis machine 102 to sound the powerfailure alarm signal at an appropriate volume (e.g., a relatively lowvolume that can be easily heard by the operator).

In another example, the audio data may indicate that significantenvironmental noise exists. The environmental noise may include generalnoise that are caused by people talking, HVAC systems running, etc. Theprocessing module 107 can instruct the speaker 101 of the hemodialysismachine 102 to sound the power failure alarm signal at an appropriatevolume (e.g., a volume that can be heard by the operator over theenvironmental noise).

In another example, the audio data may indicate that an alarm signalfrom another hemodialysis system is within audible range of themicrophone. The processing module 107 can instruct the speaker 101 ofthe hemodialysis machine 102 to sound bursts of the power failure alarmsignal at particular timings such that the bursts occur during periodsof silence of the other alarm signal. Alternatively, the processingmodule 107 can instruct the speaker 101 of the hemodialysis machine 102to sound the power failure alarm signal with an adjusted frequency suchthat the power failure alarm signal can be discerned by the operatorover the other alarm signal.

While certain implementations have been described, other implementationsare possible.

While we have described various variables that define aspects of thealarm signal which may be mandated by guidelines created and/orpublished by a standards organization, the alarm signal may be definedin other ways. In some implementations, the alarm signal is customdesigned (e.g., by the manufacturer of the dialysis machine). In someimplementations, one or more of the variables (e.g., a, x, y, t_(b),t_(d), t_(p)) can have values different than those described above.

While we have described the alarm being adjusted and emitted by ahemodialysis machine, the alarm could alternatively be adjusted andemitted by other types of medical treatment systems. Examples of othermedical treatment systems that may employ the techniques describedherein include hemofiltration systems, hemodiafiltration systems,apheresis systems, cardiopulmonary bypass systems, and peritonealdialysis systems.

Implementations of the subject matter and the functional operationsdescribed above can be implemented in other types of digital electroniccircuitry, or in computer software, firmware, or hardware, including thestructures disclosed in this specification and their structuralequivalents, or in combinations of one or more of them. Implementationsof the subject matter described in this specification can be implementedas one or more computer program products, i.e., one or more modules ofcomputer program instructions encoded on a tangible program carrier, forexample a computer-readable medium, for execution by, or to control theoperation of, a processing system. The computer readable medium can be amachine readable storage device, a machine readable storage substrate, amemory device, a composition of matter effecting a machine readablepropagated signal, or a combination of one or more of them.

The term “computer system” may encompass all apparatus, devices, andmachines for processing data, including by way of example a programmableprocessor (e.g., processing module), a computer, or multiple processorsor computers. A processing system can include, in addition to hardware,code that creates an execution environment for the computer program inquestion, e.g., code that constitutes processor firmware, a protocolstack, a database management system, an operating system, or acombination of one or more of them.

A computer program (also known as a program, software, softwareapplication, script, executable logic, or code) can be written in anyform of programming language, including compiled or interpretedlanguages, or declarative or procedural languages, and it can bedeployed in any form, including as a standalone program or as a module,component, subroutine, or other unit suitable for use in a computingenvironment. A computer program does not necessarily correspond to afile in a file system. A program can be stored in a portion of a filethat holds other programs or data (e.g., one or more scripts stored in amarkup language document), in a single file dedicated to the program inquestion, or in multiple coordinated files (e.g., files that store oneor more modules, sub programs, or portions of code). A computer programcan be deployed to be executed on one computer or on multiple computersthat are located at one site or distributed across multiple sites andinterconnected by a communication network.

Computer readable media suitable for storing computer programinstructions and data include all forms of non-volatile or volatilememory, media and memory devices, including by way of examplesemiconductor memory devices, e.g., EPROM, EEPROM, and flash memorydevices; magnetic disks, e.g., internal hard disks or removable disks ormagnetic tapes; magneto optical disks; and CD-ROM and DVD-ROM disks. Theprocessor and the memory can be supplemented by, or incorporated in,special purpose logic circuitry. The components of the system can beinterconnected by any form or medium of digital data communication,e.g., a communication network. Examples of communication networksinclude a local area network (“LAN”) and a wide area network (“WAN”),e.g., the Internet.

A number of implementations have been described. Nevertheless, it willbe understood that various modifications may be made without departingfrom the spirit and scope of the invention. Accordingly, otherimplementations are within the scope of the following claims.

1. A dialysis machine comprising: a microphone; an alert module forproducing an audible alert related to an operating condition of thedialysis machine; and a processing module configured for: receiving,from the microphone, information related to measured noise thatoriginates from a source other than the dialysis machine; determining,based on the information related to measured noise, an audible alertthat will not be masked by the measured noise when the audible alert isproduced by the alert module; and providing, to the alert module,instructions for producing the audible alert.
 2. The dialysis machine ofclaim 1, wherein the processing module is configured to identify a typeof the measured noise.
 3. The dialysis machine of claim 2, wherein themeasured noise is ambient noise.
 4. The dialysis machine of claim 2,wherein the measured noise is a second audible alert.
 5. The dialysismachine of claim 4, wherein the second audible alert is related to anoperating condition of a second dialysis machine.
 6. The dialysismachine of claim 3, wherein the information related to the ambient noiseincludes a measurement of a volume of the ambient noise.
 7. The dialysismachine of claim 6, wherein the instructions cause the alert module toproduce an audible alert that is louder than the volume of the ambientnoise.
 8. The dialysis machine of claim 4, wherein the informationrelated to the second audible alert includes a measurement of a timingof the second audible alert.
 9. The dialysis machine of claim 8, whereinthe instructions cause the alert module to produce an audible alert thathas a timing that is out of phase with the timing of the second audiblealert.
 10. The dialysis machine of claim 4, wherein the informationrelated to the second audible alert includes a measurement of afrequency of the second audible alert.
 11. The dialysis machine of claim10, wherein the instructions cause the alert module to produce anaudible alert of a frequency different from the frequency of the secondaudible alert.
 12. The dialysis machine of claim 11, wherein the audiblealert has a frequency that is within a predefined range.
 13. Thedialysis machine of claim 2, wherein the instructions for producing theaudible alert are based at least in part on the type of the measurednoise.
 14. The dialysis machine of claim 1, wherein the instructions forproducing the audible alert are based at least in part on the priorityof the audible alert.
 15. The dialysis machine of claim 14, wherein theinstructions cause the alert module to produce an audible alert that islouder than lower-priority audible alerts that are measured by themicrophone.
 16. A method comprising: receiving, from a microphone of adialysis machine, information related to measured noise that originatesfrom a source other than the dialysis machine; determining, based on theinformation related to measured noise, an audible alert related to anoperating condition of the dialysis machine, the audible alertdetermined such that the audible alert will not be masked by themeasured noise when the audible alert is produced by an alert module ofthe dialysis machine; and providing, to the alert module, instructionsfor producing the audible alert.
 17. A system comprising: a dialysismachine comprising: a microphone; an alert module for producing anaudible alert related to an operating condition of the dialysis machine;and a processing module configured for: receiving, from the microphone,information related to measured noise that originates from a sourceother than the dialysis machine; determining, based on the informationrelated to measured noise, an audible alert that will not be masked bythe measured noise when the audible alert is produced by the alertmodule; and providing, to the alert module, instructions for producingthe audible alert.
 18. A non-transitory computer-readable storage devicestoring a computer program including instructions for causing a computerto: receive, from a microphone of a dialysis machine, informationrelated to measured noise that originates from a source other than thedialysis machine; determine, based on the information related tomeasured noise, an audible alert related to an operating condition ofthe dialysis machine, the audible alert determined such that the audiblealert will not be masked by the measured noise when the audible alert isproduced by an alert module of the dialysis machine; and provide, to thealert module, instructions for producing the audible alert.